What is Java?

JAVA is a high-level programming language
developed by Sun Microsystems. Java was originally called OAK, designed
for handheld devices, but was unsuccessful. In 1995 Sun changed
the name to Java and modified the language to take
advantage of the burgeoning World Wide Web.

Java is an object-oriented programming language.
Object-oriented programming is a way of writing programs with the
common theme that the program is a collection of objects that work
together to perform the task at hand. Each object is a collection
of data and methods that manipulate
the data to perform required tasks. You will learn more about object-oriented
programming as the course progresses.

Hello
World

Open a New Project

Name the Project and Set the Location to your K:Drive

Java Comment Statements

1. Multiple line
comments

Example

/*
* This is an example of a multiple line comment
* that shows information over many lines. It begins with
a
* slash and an asterisk and ends with an asterisk and
a slash
*/

2. Single line comments

// This
comment type is used for short one line comments

Using System.out.println

System.out.println ("Hello World");
is responsible for outputting words to the screen.

The function:System.out.println( );

The function System.out.println(
); takes letters (strings)
or values (numbers) as a parameter and displays
it on the screen (anything inside of the ( ) is displayed). You
can display more than one string or numeric by joining them together
using the "+" operator.

Example

System.out.println("Hello
" + "how are you today");

This code will print out the phrase "Hello
how are you today" on the screen by joining the two strings
together into one line of output.

System.out.println("Your
age is " + 21);

This code will print out the phrase "Your
age is 21" on the screen by joining the string and the
numeric together into one line of output.

Printing special characters using
the System.out.println(); function:

Certain ASCII characters that are difficult
to represent in a string either because they are not viewable (like
an enter key) or because they are part of the formatting of strings
in Java (like a " or a ' or a \ ) may be displayed using an ASCII
character code or control code.

Shown below is
a chart listing of some common control codes:

Control
Code

What
it means

\n

new line

\r

return
character

\t

tab

\b

backspace

\"

double
quote

\'

single
quote

\\

backslash

Example

If you wanted to print the phrase Go
"SENS" Go (quotes around SENS) on the screen, you would
use the code:

System.out.println("Go
\" SENS \" Go");

If you wanted to print GO on one line, SENS
on another line and Go on a third line you could use the code: